Plastic mulching has been widely utilized to enhance crop yield but generates persistent plastic residues that threaten agricultural sustainability. To address this challenge, a biodegradable and sprayable liquid mulching of carboxymethyl cellulose (CMC)-based 'aquo-bioplastic' derived from renewable rotten bamboo was developed. Natural deconstruction remodeled the bamboo cell walls, enhancing cellulose accessibility by providing cellulose with lower crystallinity, less degree of polymerization, and more exposed reactive hydroxyl groups for efficient etherification into CMC, and subsequent crosslinking with glutaraldehyde for aquo-bioplastic. The resulting aquo-bioplastic exhibited strong mechanical properties (75.5 MPa of tensile strength and 527.6 MPa of Young's modulus) and excellent air resistance (0.003 μm/Pa·s) exceeding reported bio-plastic films. Furthermore, the aquo-bioplastic was facilely applied into the field by drone spraying, enabling automated mulching and promoting soil moisture, temperature, seed germination, and eventually crop growth. Following field application, the aquo-bioplastic has been completely biodegraded within 64 days in soil, eliminating the requirement for post-harvest mulch removal. These results collectively suggest that CMC-based aquo-bioplastic derived from rotten bamboo could serve as an alternative of traditional plastic mulch to tackle white pollution and promote sustainable agriculture.

Cellulose-based smart materials hold great promise for applications in the field of flexible electronics. Simultaneously realizing multiple stimulus-responsive functionalities while preserving the outstanding mechanical properties of cellulose-based smart materials remains a considerable challenge. High-performance cellulose-based elastomers integrating thermochromic, mechanochromic, hydrochromic, and water deformation capabilities were successfully fabricated through a simple synthetic strategy. Thermochromic response is remarkably rapid, occurring within 5 s at a transition temperature of 35 °C. The response temperature is close to human physiological temperature, and demonstrated excellent reversibility and repeatability. Mechanochromic behavior exhibited a visual color change from red to white upon stretching. Meanwhile, during the mechanochromic process, cellulose-based elastomer achieved an outstanding elongation at break of up to 1800%. Furthermore, water deformation allowed for controllable bending and gripping functions. Given these multifunctional properties, cellulose-based elastomer shows great potential in the field of smart bionic prosthetics, as it could simultaneously perform complex functions such as temperature sensing, joint deformation monitoring, and underwater grasping, thereby providing new design insights for the development of next-generation intelligent biomimetic materials.

Renewable salinity-gradient osmotic energy can be converted to electric energy by using the reverse electrodialysis (RED) technique, where the ion-exchange membranes (IEMs) play an important role in enhancing the output power for osmotic energy harvesting. To enhance the efficiency of the RED system, numerous advanced membrane materials have been investigated for fabricating high-performance IEMs. In recent years, nanocelluloses with abundant sources, active functional groups, and high-aspect-ratio have emerged as the ideal platform for developing various sustainable, high-performance nanocellulose-based IEMs used in the RED process. The review comprehensively summarized the current research progress of nanocellulose-based IEMs used in the RED process, from the preparation and modification techniques of nanocelluloses, manufacturing processes of nanocellulose-based hybrid/composite IEMs, to their RED performance, such as ion selectivity, output power density, and durability. We also discuss the operational principles of RED from the RED cell, the RED stack, and the property index of the RED process. We finally outline the perspective and challenges for RED-used nanocellulose-based IEMs for the potential practical application of the salinity-gradient osmotic energy conversion.

Microfibrillated cellulose (MFC) has attracted increasing attention as a sustainable reinforcement for polymer composites. However, when incorporated into hydrophobic thermoplastics such as acrylonitrile–butadiene–styrene (ABS), MFC often improves tensile strength but significantly reduces elongation at break. To address this challenge, we designed a surface modification strategy for MFC. Leaf bleached kraft pulp (LBKP) was first carboxyethylated and mechanically fibrillated to produce carboxyethylated MFC (C-MFC), which was subsequently amidated with octadecylamine (ODA) to obtain hydrophobized octadecylamine-modified carboxyethyl MFC (OC-MFC). Composite films of OC-MFC/ABS were fabricated by solution casting followed by hot pressing. The structures and properties of MFC, C-MFC, OC-MFC, and OC-MFC/ABS composites were systematically characterized using laser particle size analysis, FTIR, dynamic water contact angle, tensile testing, thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The results demonstrated that ODA modification effectively increased the hydrophobicity of MFC, leading to improved dispersion and interfacial compatibility with the ABS matrix. Mechanical testing revealed that the incorporation of 0.5–1 wt

Calcium hydroxide was used as a swelling agent and grinding aid to grind together with cellulose raw materials to prepare microfibrillated cellulose (MFC). Carbon dioxide was introduced to obtain MFC coated with calcium carbonate (CMFC). The effect of calcium hydroxide dosage on the fibrillation process of cellulose materials and the characteristics of MFCs and CMFCs were studied. Results show that when the dosage of calcium hydroxide was 5 % (based on cellulose materials), calcium hydroxide could be completely dissolved in water and had a swelling effect on cellulose materials. When the dosage reached 10 %, undissolved calcium hydroxide particles could serve as grinding media to assist in the fibrillation of cellulose materials. When the dosage exceeded 50 %, the auxiliary grinding effect of calcium hydroxide was more obvious. After accelerated carbonation, the generated calcium carbonate nanoparticles were coated on the surface of MFC, which increased its viscosity and decreased water retention value. The presence of calcium carbonate also facilitated the concentration, redispersion, and drying of MFC. The pretreatment, mechanical fibrillation, and accelerated carbonation were carried out in the same equipment without the need for heating or washing. Therefore, this study provides a in situ and one step method for the preparation of MFC.

Poly(butylene adipate-co-terephthalate) (PBAT) is one of the most suitable aliphatic–aromatic co-polyesters to replace traditional plastics due to its excellent properties and biodegradability. However, the relatively low mechanical properties limit its large-scale application. Nanocellulose has been attempted to be chemically modified and used to enhance PBAT, but few significant results have been achieved. In this study, three octadecylamine-modified carboxyethyl cellulose microfibrils (OC-CMFs) with different degrees of substitution (DS) were successfully prepared and used to enhance PBAT. The microstructure, chemical structure, hydrophobicity, and thermal stability of the prepared OC-CMFs, as well as the mechanical properties, microstructure, and thermal properties of the OC-CMFs/PBAT composites were characterized. The results show that OC-CMFs have high hydrophobicity, with a water contact angle of up to 132.2°, making them highly dispersed and compatible in the PBAT matrix. When 0.5 wt

Pulp and paper are gradually transforming from a traditional industry into a new green strategic industry. In parallel, cellulose-derived transparent paper is gaining ground for the development of advanced functional materials for light management with eco-friendly, high performance, and multifunctionality. This review focuses on methods and processes for the preparation of cellulose-derived transparent papers, highlighting the characterization of raw materials linked to responses to different properties, such as optical and mechanical properties. The applications in electronic devices, energy conversion and storage, and eco-friendly packaging are also highlighted with the objective to showcase the untapped potential of cellulose-derived transparent paper, challenging the prevailing notion that paper is merely a daily life product. Finally, the challenges and propose future directions for the development of cellulose-derived transparent paper are identified.

To improve the performance of polyurethane films,small amounts of cellulose nanofibrils(CNF)were physically blended with a waterborne polyurethane(WPU)emulsion,and then CNF/WPU composite films were prepared by cast-coating and drying.The particle size of the emulsions and the chemical structure,micromorphology,thermal stability,mechanical properties,and water resistance of the composite films were characterized using a Malvern laser particle size analyzer,Fourier transform infrared spectroscopy(FT-IR),scanning electron microscopy(SEM),thermogravimetric analysis(TGA),an electronic strength machine,water contact angle analysis(WCA),and water absorption tests,respectively.The results showed that at a low CNF content of 0.3 wt％,the particle size of the WPU emulsion and chemical structure of the film did not change significantly.In addition,the tensile strength of the composite film increased by up to 108％compared to the neat WPU film,and the thermal stability and water resistance were slightly improved.The addition of CNF greatly enhanced the tensile strength while maintaining the other original properties of the WPU film,which may greatly improve the service life and tear resistance of commercial coatings in the future.

Waterborne coatings often delaminate and settle during long-term storage,requiring the addition of thickeners.The effects of nanofibrillated cellulose(NFC)and the commonly used thickener,hydroxyethyl cellulose(HEC),on the storage stability of waterborne coatings were compared in this study.The morphology of NFC was characterized using infrared spectroscopy(FT-IR)and scanning electron microscopy(SEM).The rotational viscosity and rheological properties of the waterborne coatings with NFC and HEC were tested.Stationary settling experiments were also conducted at different temperatures to compare the difference of NFC and HEC on improving the storage stability of the waterborne coatings.The results showed that the waterborne coating with NFC exhibited pseudoplastic fluid characteristics;a small addition of NFC can achieve the same improvement effect on the storage stability of waterborne coatings as HEC.Further,the improvement effect of NFC was not affected by temperature.The waterborne coating with NFC still exhibited good storage stability at high temperatures,which was significantly superior to that of HEC.Therefore,NFC is a feasible agent for improving the prolonged storage stability and warming-induced delamination of waterborne coatings.

Nanofibrillated celluloses (NFC) have attracted tremendous attention as nanofillers to improve the mechanical properties of waterborne resin. In this study, NFC was prepared by mechanical fibrillation, and then modified respectively with three different types of silane coupling agents: ?-aminopropyltriethoxysilane (KH550), ?-(2, 3-epoxypropoxy) propyl trimethoxysilane (KH560), and ?-(methacryloyloxy) propyl trimethoxysilane (KH570). The obtained NFC and modified NFCs were physically mixed with water-based acrylic resin (WAR) to prepare films by casting method. The NFC, silanized NFC, and films were analyzed by Malvern laser particle sizer, scanning electron microscopy (SEM), Fourier transform infrared (FTIR), thermogravimetric analyzer (TGA), water contact angle (WCA), rotational rheometer, and power stretchers, respectively. Results showed that NFCs were successfully prepared and modified. The KH570 modified NFC had a slightly smaller particle size, higher absolute Zeta potential and yield stress values, good thermal stability, and exhibited better dispersion and suspension stability in solution. However, the NFC modified by KH560 had the best improvement effect on the mechanical properties and hydrophobicity of WAR membranes. Adding only 0.3 wt% KH560 modified NFC could increase the tensile strength of WAR film by 131.9%, and the WCA of the film could be increased from 85.2 & DEG; to 101.6 & DEG;, which makes this study beneficial for promoting the application of nanofibrillated cellulose in WAR.

根据 Smithers公司发布的数据,2021年全球特种纸产量为2509万t,市场充满活力,在未来5年内将提供多种利润丰厚的多样化机会.这包括提供新的包装产品以替代塑料,以及提供新产品以满足过滤、电池和电气绝缘纸等工业需求与应用.预计未来5年特种纸将以2.4％的复合年均增长率稳步增长,2026年需求将达到2826万t.

2021年,南非回收了 115万t废纸和纸包装制品,纸张回收率为61.4％. 南非造纸制造商协会(PAMSA)执行主任Jane Molony表示:"2021废纸回收率比前一年下降了 9％,这主要是由于2020-2021年新冠疫情导致的供应链中断,以及经济形势和购买方式的转变."

Biodegradable polymers such as poly(butylene adipate-co-terephthalate) (PBAT) have attracted great interest as alternatives to traditional petroleum-based polymers. Nonetheless, it is necessary to improve some properties of PBAT, such as mechanical strength. Cellulose nanofiber (CNF) can improve PBAT mechanical strength, but its dispersion and compatibility in the PBAT matrix require further improvement. In this study, octadecylamine (ODA) was utilized to graft-modify CNF to change the fiber-to-fiber interaction and improve its compatibility with the PBAT matrix. PBAT composites with 1 wt％ CNF were prepared using a masterbatch premixing method to avoid CNF aggregation during extrusion. The effects of ODA graft modification on CNF properties were studied;varying degrees of CNF modification were investigated for their effect on PBAT properties. ODA-modified CNF (OCNF)/PBAT melt-extruded composites possessing 17.2％higher tensile strength than pure PBAT polymer were obtained without affecting the thermal stability of PBAT. As a result, surface modification of CNF with ODA is an effective strategy for improving CNF-PBAT compatibility.

In this study,lignin-containing microfibrillated cellulose(MFC)was prepared from corncob residue after xylose extraction via co-grinding with calcium hydroxide.The product was then compared with the MFC obtained by direct grinding and applied to strengthen paper.The chemical composition and morphological structure analysis results showed that the corncob residue can be used to prepare lignin-containing MFC and does not require further purification.Moreover,the co-grinding with calcium hydroxide is easier to fibrillate corncob residue.The MFC obtained by co-grinding with calcium hydroxide had a higher aspect ratio,and its surface was coated with calcium carbonate nanoparticles.MFCs obtained by both the methods mentioned above had an obvious strengthening effect on paper.Compared with the paper without MFC,the tensile index,elongation,burst index,and folding strength of the paper with MFC obtained by co-grinding with calcium hydroxide significantly increased by 17.5％,22.1％,19.5％,and 157.1％,respectively.This study provides a novel idea for the utilization of corncob residue,which may enhance the value and promote the comprehensive utilization of corn by-products.

随着欧洲经济放缓和防疫限制,2020年欧洲纸张和纸板消费量总计7100万t,比2019年下降了 5.3％.2020年,欧洲造纸工业联合会(Cepi)成员国纸和纸板总产量8520万t,与2019年相比下滑了 4.8％.这一下降趋势也存在于世界许多国家和地区,如美国、日本、巴西和加拿大等.

纳米纤维素具有高长径比、高结晶度、高杨氏模量、高强度等优点,加之其具有生物质材料的轻质、可降解及可再生等特性,使其成为一种改善水性涂料机械、光学、耐水等性能的优异选择.本文综述了纳米纤维素制备和改性方法,详细论述了纤维素纳米纤丝(CNF)和纤维素纳米晶体(CNC)对水性聚氨酯和水性丙烯酸涂料的性能改善机理及其应用研究进展.最后总结了纳米纤维素复合水性涂料研究现存的问题,并总结了未来的研究方向.

6月16日,Sappi Europe宣布将上调所有等级的涂布热升华纸（Transjet）、未涂布热升华纸（Basejet）和喷墨打印纸（Inkjet）价格,涨幅为8%～15%。新价格对2021年7月1日起交货的产品生效。

Carboxyethylation pretreatment was used to prepare microfibrillated cellulose（MFC） in this study. In order to evaluate the adaptability of this pretreatment method, carboxyethylated MFC was prepared from six different cellulosic materials. The carboxyl content, degree of polymerization, water retention value, charge density, chemical structure,size distribution, and micromorphology of the materials before and after pretreatment and grinding were studied and compared. The viscosity,ultraviolet（UV） transmittance, and thermal stability of the MFC samples at a certain concentration were determined. The results showed that the carboxyl content, water retention value, charge density, degree of polymerization, size distribution, and micromorphology of the pretreated and ground samples varied with those of the raw materials. The initial viscosity varied based on the type of raw material used. The MFC suspension prepared from cotton linter pulp had the highest UV transmittance, while the MFC prepared from bleached softwood kraft pulp had the highest viscosity at a low shear rate.After thermal degradation, the amount of residual char from the MFC prepared with the thermo-mechanical pulp was slightly higher than that of the other MFCs. This study demonstrates that carboxyethylation is an effective pretreatment method for different cellulosic materials.

玉米芯提取木糖后剩余的残渣富含纤维素和木质素,采用羧乙基化反应和质量分数1％的NaOH溶液分别对玉米芯渣进行预处理,再经机械解离制备了纳米纤维素,最后经棒涂法制得纳米纤维素膜,并对预处理前后玉米芯渣、纳米纤维素及其膜的化学结构、组分含量、微观形貌、尺寸分布、水接触角和热稳定性进行了分析和表征.结果表明,羧乙基化预处理可增加玉米芯渣的羧基含量,同时脱除部分木质素,而碱预处理可脱除大部分木质素.经预处理后,玉米芯渣纤维尺寸明显降低、可及度增加.经机械解离后,羧乙基化预处理所得纳米纤维素的直径更小、分布更均匀,其经棒涂法所得膜也更加致密平滑,水接触角较大.另外,两种预处理方法均降低了所得纳米纤维素膜的热稳定性.

In this study,carboxyethyl microfibrillated cellulose/graphene composite film,carboxyethyl microfibrillated cellulose/polyaniline composite film,and carboxyethyl microfibrillated cellulose/graphene/polyaniline composite film were prepared respectively by physical mix-ing method,chemical in-situ adsorption polymerization method,and the combination of physical blending and chemical in-situ adsorption po-lymerization method using coating forming method with carboxyethyl microfibrillated cellulose as matrix.The micro morphology,chemical structure,hydrophobicity,thermal stability,mechanical and electrochemical properties of the film were characterized.The results showed that carboxyethyl microfibrillated cellulose had good film-forming property and could act as carrier and dispersant.After compounding gra-phene or polyaniline,the mechanical and electrochemical properties of the composite film increased significantly,among which,graphene could improve the thermal stability of the film,while polyaniline could increase the hydrophobicity of the film.In addition,when 10%gra-phene and 30%polyaniline were compounded,it showed a synergistic effect on the electrochemical properties of the carboxyethyl microfibril-lated cellulose/graphene/polyaniline composite film.